Seasickness is a result of a conflict in the inner ear, where the human balance mechanism resides, and is caused by a vessel's erratic motion on the water.
noun [具体名词]晕船
He was very prone to seasickness and already felt queasy. 他很容易晕船,此时已经感到恶心了。
seasickness
“ -ness” ⌜ 表示状态或质量的性质 - indicating the state or quality of ~ ⌟